Pub Date : 2024-05-08DOI: 10.1007/s00401-024-02717-x
Klaus Schmierer, Hans Lassmann
{"title":"The shoulders we keep standing on: remembering Otto Marburg, a big brain in neurology and multiple sclerosis, at 150.","authors":"Klaus Schmierer, Hans Lassmann","doi":"10.1007/s00401-024-02717-x","DOIUrl":"10.1007/s00401-024-02717-x","url":null,"abstract":"","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140875540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-07DOI: 10.1007/s00401-024-02737-7
Mirte Scheper, Frederik N. F. Sørensen, Gabriele Ruffolo, Alessandro Gaeta, Lilian J. Lissner, Jasper J. Anink, Irina Korshunova, Floor E. Jansen, Kate Riney, Wim van Hecke, Angelika Mühlebner, Konstantin Khodosevich, Dirk Schubert, Eleonora Palma, James D. Mills, Eleonora Aronica
GABAergic interneurons play a critical role in maintaining neural circuit balance, excitation–inhibition regulation, and cognitive function modulation. In tuberous sclerosis complex (TSC), GABAergic neuron dysfunction contributes to disrupted network activity and associated neurological symptoms, assumingly in a cell type-specific manner. This GABAergic centric study focuses on identifying specific interneuron subpopulations within TSC, emphasizing the unique characteristics of medial ganglionic eminence (MGE)- and caudal ganglionic eminence (CGE)-derived interneurons. Using single-nuclei RNA sequencing in TSC patient material, we identify somatostatin-expressing (SST+) interneurons as a unique and immature subpopulation in TSC. The disrupted maturation of SST+ interneurons may undergo an incomplete switch from excitatory to inhibitory GABAergic signaling during development, resulting in reduced inhibitory properties. Notably, this study reveals markers of immaturity specifically in SST+ interneurons, including an abnormal NKCC1/KCC2 ratio, indicating an imbalance in chloride homeostasis crucial for the postsynaptic consequences of GABAergic signaling as well as the downregulation of GABAA receptor subunits, GABRA1, and upregulation of GABRA2. Further exploration of SST+ interneurons revealed altered localization patterns of SST+ interneurons in TSC brain tissue, concentrated in deeper cortical layers, possibly linked to cortical dyslamination. In the epilepsy context, our research underscores the diverse cell type-specific roles of GABAergic interneurons in shaping seizures, advocating for precise therapeutic considerations. Moreover, this study illuminates the potential contribution of SST+ interneurons to TSC pathophysiology, offering insights for targeted therapeutic interventions.
{"title":"Impaired GABAergic regulation and developmental immaturity in interneurons derived from the medial ganglionic eminence in the tuberous sclerosis complex","authors":"Mirte Scheper, Frederik N. F. Sørensen, Gabriele Ruffolo, Alessandro Gaeta, Lilian J. Lissner, Jasper J. Anink, Irina Korshunova, Floor E. Jansen, Kate Riney, Wim van Hecke, Angelika Mühlebner, Konstantin Khodosevich, Dirk Schubert, Eleonora Palma, James D. Mills, Eleonora Aronica","doi":"10.1007/s00401-024-02737-7","DOIUrl":"https://doi.org/10.1007/s00401-024-02737-7","url":null,"abstract":"<p>GABAergic interneurons play a critical role in maintaining neural circuit balance, excitation–inhibition regulation, and cognitive function modulation. In tuberous sclerosis complex (TSC), GABAergic neuron dysfunction contributes to disrupted network activity and associated neurological symptoms, assumingly in a cell type-specific manner. This GABAergic centric study focuses on identifying specific interneuron subpopulations within TSC, emphasizing the unique characteristics of medial ganglionic eminence (MGE)- and caudal ganglionic eminence (CGE)-derived interneurons. Using single-nuclei RNA sequencing in TSC patient material, we identify somatostatin-expressing (SST+) interneurons as a unique and immature subpopulation in TSC. The disrupted maturation of SST+ interneurons may undergo an incomplete switch from excitatory to inhibitory GABAergic signaling during development, resulting in reduced inhibitory properties. Notably, this study reveals markers of immaturity specifically in SST+ interneurons, including an abnormal <i>NKCC1/KCC2</i> ratio, indicating an imbalance in chloride homeostasis crucial for the postsynaptic consequences of GABAergic signaling as well as the downregulation of GABA<sub>A</sub> receptor subunits, <i>GABRA1</i>, and upregulation of <i>GABRA2.</i> Further exploration of SST+ interneurons revealed altered localization patterns of SST+ interneurons in TSC brain tissue, concentrated in deeper cortical layers, possibly linked to cortical dyslamination. In the epilepsy context, our research underscores the diverse cell type-specific roles of GABAergic interneurons in shaping seizures, advocating for precise therapeutic considerations. Moreover, this study illuminates the potential contribution of SST+ interneurons to TSC pathophysiology, offering insights for targeted therapeutic interventions.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140875157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-05DOI: 10.1007/s00401-024-02735-9
Hailong Song, Alexandra Tomasevich, Andrew Paolini, Kevin D. Browne, Kathryn L. Wofford, Brian Kelley, Eashwar Kantemneni, Justin Kennedy, Yue Qiu, Andrea L. C. Schneider, Jean-Pierre Dolle, D. Kacy Cullen, Douglas H. Smith
Although human females appear be at a higher risk of concussion and suffer worse outcomes than males, underlying mechanisms remain unclear. With increasing recognition that damage to white matter axons is a key pathologic substrate of concussion, we used a clinically relevant swine model of concussion to explore potential sex differences in the extent of axonal pathologies. At 24 h post-injury, female swine displayed a greater number of swollen axonal profiles and more widespread loss of axonal sodium channels than males. Axon degeneration for both sexes appeared to be related to individual axon architecture, reflected by a selective loss of small caliber axons after concussion. However, female brains had a higher percentage of small caliber axons, leading to more extensive axon loss after injury compared to males. Accordingly, sexual dimorphism in axonal size is associated with more extensive axonal pathology in females after concussion, which may contribute to worse outcomes.
{"title":"Sex differences in the extent of acute axonal pathologies after experimental concussion","authors":"Hailong Song, Alexandra Tomasevich, Andrew Paolini, Kevin D. Browne, Kathryn L. Wofford, Brian Kelley, Eashwar Kantemneni, Justin Kennedy, Yue Qiu, Andrea L. C. Schneider, Jean-Pierre Dolle, D. Kacy Cullen, Douglas H. Smith","doi":"10.1007/s00401-024-02735-9","DOIUrl":"https://doi.org/10.1007/s00401-024-02735-9","url":null,"abstract":"<p>Although human females appear be at a higher risk of concussion and suffer worse outcomes than males, underlying mechanisms remain unclear. With increasing recognition that damage to white matter axons is a key pathologic substrate of concussion, we used a clinically relevant swine model of concussion to explore potential sex differences in the extent of axonal pathologies. At 24 h post-injury, female swine displayed a greater number of swollen axonal profiles and more widespread loss of axonal sodium channels than males. Axon degeneration for both sexes appeared to be related to individual axon architecture, reflected by a selective loss of small caliber axons after concussion. However, female brains had a higher percentage of small caliber axons, leading to more extensive axon loss after injury compared to males. Accordingly, sexual dimorphism in axonal size is associated with more extensive axonal pathology in females after concussion, which may contribute to worse outcomes.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140845233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-02DOI: 10.1007/s00401-024-02727-9
Nurun N. Fancy, Amy M. Smith, Alessia Caramello, Stergios Tsartsalis, Karen Davey, Robert C. J. Muirhead, Aisling McGarry, Marion H. Jenkyns, Eleonore Schneegans, Vicky Chau, Michael Thomas, Sam Boulger, To Ka Dorcas Cheung, Emily Adair, Marianna Papageorgopoulou, Nanet Willumsen, Combiz Khozoie, Diego Gomez-Nicola, Johanna S. Jackson, Paul M. Matthews
Aging is associated with cell senescence and is the major risk factor for AD. We characterized premature cell senescence in postmortem brains from non-diseased controls (NDC) and donors with Alzheimer’s disease (AD) using imaging mass cytometry (IMC) and single nuclear RNA (snRNA) sequencing (> 200,000 nuclei). We found increases in numbers of glia immunostaining for galactosidase beta (> fourfold) and p16INK4A (up to twofold) with AD relative to NDC. Increased glial expression of genes related to senescence was associated with greater β-amyloid load. Prematurely senescent microglia downregulated phagocytic pathways suggesting reduced capacity for β-amyloid clearance. Gene set enrichment and pseudo-time trajectories described extensive DNA double-strand breaks (DSBs), mitochondrial dysfunction and ER stress associated with increased β-amyloid leading to premature senescence in microglia. We replicated these observations with independent AD snRNA-seq datasets. Our results describe a burden of senescent glia with AD that is sufficiently high to contribute to disease progression. These findings support the hypothesis that microglia are a primary target for senolytic treatments in AD.
{"title":"Characterisation of premature cell senescence in Alzheimer’s disease using single nuclear transcriptomics","authors":"Nurun N. Fancy, Amy M. Smith, Alessia Caramello, Stergios Tsartsalis, Karen Davey, Robert C. J. Muirhead, Aisling McGarry, Marion H. Jenkyns, Eleonore Schneegans, Vicky Chau, Michael Thomas, Sam Boulger, To Ka Dorcas Cheung, Emily Adair, Marianna Papageorgopoulou, Nanet Willumsen, Combiz Khozoie, Diego Gomez-Nicola, Johanna S. Jackson, Paul M. Matthews","doi":"10.1007/s00401-024-02727-9","DOIUrl":"https://doi.org/10.1007/s00401-024-02727-9","url":null,"abstract":"<p>Aging is associated with cell senescence and is the major risk factor for AD. We characterized premature cell senescence in postmortem brains from non-diseased controls (NDC) and donors with Alzheimer’s disease (AD) using imaging mass cytometry (IMC) and single nuclear RNA (snRNA) sequencing (> 200,000 nuclei). We found increases in numbers of glia immunostaining for galactosidase beta (> fourfold) and p16<sup>INK4A</sup> (up to twofold) with AD relative to NDC. Increased glial expression of genes related to senescence was associated with greater β-amyloid load. Prematurely senescent microglia downregulated phagocytic pathways suggesting reduced capacity for β-amyloid clearance. Gene set enrichment and pseudo-time trajectories described extensive DNA double-strand breaks (DSBs), mitochondrial dysfunction and ER stress associated with increased β-amyloid leading to premature senescence in microglia. We replicated these observations with independent AD snRNA-seq datasets. Our results describe a burden of senescent glia with AD that is sufficiently high to contribute to disease progression. These findings support the hypothesis that microglia are a primary target for senolytic treatments in AD.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140819274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Influenza-associated encephalopathy (IAE) is extremely acute in onset, with high lethality and morbidity within a few days, while the direct pathogenesis by influenza virus in this acute phase in the brain is largely unknown. Here we show that influenza virus enters into the cerebral endothelium and thereby induces IAE. Three-weeks-old young mice were inoculated with influenza A virus (IAV). Physical and neurological scores were recorded and temporal-spatial analyses of histopathology and viral studies were performed up to 72 h post inoculation. Histopathological examinations were also performed using IAE human autopsy brains. Viral infection, proliferation and pathogenesis were analyzed in cell lines of endothelium and astrocyte. The effects of anti-influenza viral drugs were tested in the cell lines and animal models. Upon intravenous inoculation of IAV in mice, the mice developed encephalopathy with brain edema and pathological lesions represented by micro bleeding and injured astrocytic process (clasmatodendrosis) within 72 h. Histologically, massive deposits of viral nucleoprotein were observed as early as 24 h post infection in the brain endothelial cells of mouse models and the IAE patients. IAV inoculated endothelial cell lines showed deposition of viral proteins and provoked cell death, while IAV scarcely amplified. Inhibition of viral transcription and translation suppressed the endothelial cell death and the lethality of mouse models. These data suggest that the onset of encephalopathy should be induced by cerebral endothelial infection with IAV. Thus, IAV entry into the endothelium, and transcription and/or translation of viral RNA, but not viral proliferation, should be the key pathogenesis of IAE.
{"title":"Viral entry and translation in brain endothelia provoke influenza-associated encephalopathy","authors":"Shihoko Kimura-Ohba, Mieko Kitamura, Yusuke Tsukamoto, Shigetoyo Kogaki, Shinsuke Sakai, Hiroaki Fushimi, Keiko Matsuoka, Makoto Takeuchi, Kyoko Itoh, Keiji Ueda, Tomonori Kimura","doi":"10.1007/s00401-024-02723-z","DOIUrl":"https://doi.org/10.1007/s00401-024-02723-z","url":null,"abstract":"<p>Influenza-associated encephalopathy (IAE) is extremely acute in onset, with high lethality and morbidity within a few days, while the direct pathogenesis by influenza virus in this acute phase in the brain is largely unknown. Here we show that influenza virus enters into the cerebral endothelium and thereby induces IAE. Three-weeks-old young mice were inoculated with influenza A virus (IAV). Physical and neurological scores were recorded and temporal-spatial analyses of histopathology and viral studies were performed up to 72 h post inoculation. Histopathological examinations were also performed using IAE human autopsy brains. Viral infection, proliferation and pathogenesis were analyzed in cell lines of endothelium and astrocyte. The effects of anti-influenza viral drugs were tested in the cell lines and animal models. Upon intravenous inoculation of IAV in mice, the mice developed encephalopathy with brain edema and pathological lesions represented by micro bleeding and injured astrocytic process (clasmatodendrosis) within 72 h. Histologically, massive deposits of viral nucleoprotein were observed as early as 24 h post infection in the brain endothelial cells of mouse models and the IAE patients. IAV inoculated endothelial cell lines showed deposition of viral proteins and provoked cell death, while IAV scarcely amplified. Inhibition of viral transcription and translation suppressed the endothelial cell death and the lethality of mouse models. These data suggest that the onset of encephalopathy should be induced by cerebral endothelial infection with IAV. Thus, IAV entry into the endothelium, and transcription and/or translation of viral RNA, but not viral proliferation, should be the key pathogenesis of IAE.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140814435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the CNS characterized by the production of disease-specific autoantibodies against aquaporin-4 (AQP4) water channels. Animal model studies suggest that anti-AQP4 antibodies cause a loss of AQP4-expressing astrocytes, primarily via complement-dependent cytotoxicity. Nonetheless, several aspects of the disease remain unclear, including: how anti-AQP4 antibodies cross the blood–brain barrier from the periphery to the CNS; how NMOSD expands into longitudinally extensive transverse myelitis or optic neuritis; how multiphasic courses occur; and how to prevent attacks without depleting circulating anti-AQP4 antibodies, especially when employing B-cell-depleting therapies. To address these knowledge gaps, we conducted a comprehensive ‘stage-dependent’ investigation of immune cell elements in situ in human NMOSD lesions, based on neuropathological techniques for autopsied/biopsied CNS materials. The present study provided three major findings. First, activated or netting neutrophils and melanoma cell adhesion molecule-positive (MCAM+) helper T (TH) 17/cytotoxic T (TC) 17 cells are prominent, and the numbers of these correlate with the size of NMOSD lesions in the initial or early-active stages. Second, forkhead box P3-positive (FOXP3+) regulatory T (Treg) cells are recruited to NMOSD lesions during the initial, early-active or late-active stages, suggesting rapid suppression of proinflammatory autoimmune events in the active stages of NMOSD. Third, compartmentalized resident memory immune cells, including CD103+ tissue-resident memory T (TRM) cells with long-lasting inflammatory potential, are detected under “standby” conditions in all stages. Furthermore, CD103+ TRM cells express high levels of granzyme B/perforin-1 in the initial or early-active stages of NMOSD in situ. We infer that stage-dependent compartmentalized immune traits orchestrate the pathology of anti-AQP4 antibody-guided NMOSD in situ. Our work further suggests that targeting activated/netting neutrophils, MCAM+ TH17/TC17 cells, and CD103+ TRM cells, as well as promoting the expansion of FOXP3+ Treg cells, may be effective in treating and preventing relapses of NMOSD.
{"title":"Stage-dependent immunity orchestrates AQP4 antibody-guided NMOSD pathology: a role for netting neutrophils with resident memory T cells in situ","authors":"Akihiro Nakajima, Fumihiro Yanagimura, Etsuji Saji, Hiroshi Shimizu, Yasuko Toyoshima, Kaori Yanagawa, Musashi Arakawa, Mariko Hokari, Akiko Yokoseki, Takahiro Wakasugi, Kouichirou Okamoto, Hirohide Takebayashi, Chihiro Fujii, Kyoko Itoh, Yo-ichi Takei, Shinji Ohara, Mitsunori Yamada, Hitoshi Takahashi, Masatoyo Nishizawa, Hironaka Igarashi, Akiyoshi Kakita, Osamu Onodera, Izumi Kawachi","doi":"10.1007/s00401-024-02725-x","DOIUrl":"https://doi.org/10.1007/s00401-024-02725-x","url":null,"abstract":"<p>Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the CNS characterized by the production of disease-specific autoantibodies against aquaporin-4 (AQP4) water channels. Animal model studies suggest that anti-AQP4 antibodies cause a loss of AQP4-expressing astrocytes, primarily via complement-dependent cytotoxicity. Nonetheless, several aspects of the disease remain unclear, including: how anti-AQP4 antibodies cross the blood–brain barrier from the periphery to the CNS; how NMOSD expands into longitudinally extensive transverse myelitis or optic neuritis; how multiphasic courses occur; and how to prevent attacks without depleting circulating anti-AQP4 antibodies, especially when employing B-cell-depleting therapies. To address these knowledge gaps, we conducted a comprehensive ‘stage-dependent’ investigation of immune cell elements in situ in human NMOSD lesions, based on neuropathological techniques for autopsied/biopsied CNS materials. The present study provided three major findings. First, activated or netting neutrophils and melanoma cell adhesion molecule-positive (MCAM<sup>+</sup>) helper T (T<sub>H</sub>) 17/cytotoxic T (T<sub>C</sub>) 17 cells are prominent, and the numbers of these correlate with the size of NMOSD lesions in the initial or early-active stages. Second, forkhead box P3-positive (FOXP3<sup>+</sup>) regulatory T (T<sub>reg</sub>) cells are recruited to NMOSD lesions during the initial, early-active or late-active stages, suggesting rapid suppression of proinflammatory autoimmune events in the active stages of NMOSD. Third, compartmentalized resident memory immune cells, including CD103<sup>+</sup> tissue-resident memory T (T<sub>RM</sub>) cells with long-lasting inflammatory potential, are detected under “standby” conditions in all stages. Furthermore, CD103<sup>+</sup> T<sub>RM</sub> cells express high levels of granzyme B/perforin-1 in the initial or early-active stages of NMOSD in situ. We infer that stage-dependent compartmentalized immune traits orchestrate the pathology of anti-AQP4 antibody-guided NMOSD in situ. Our work further suggests that targeting activated/netting neutrophils, MCAM<sup>+</sup> T<sub>H</sub>17/T<sub>C</sub>17 cells, and CD103<sup>+</sup> T<sub>RM</sub> cells, as well as promoting the expansion of FOXP3<sup>+</sup> T<sub>reg</sub> cells, may be effective in treating and preventing relapses of NMOSD.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140642552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-24DOI: 10.1007/s00401-024-02730-0
Anastasia Geladaris, Sebastian Torke, Darius Saberi, Yasemin B. Alankus, Frank Streit, Sabrina Zechel, Christine Stadelmann-Nessler, Andreas Fischer, Ursula Boschert, Darius Häusler, Martin S. Weber
In multiple sclerosis (MS), persisting disability can occur independent of relapse activity or development of new central nervous system (CNS) inflammatory lesions, termed chronic progression. This process occurs early and it is mostly driven by cells within the CNS. One promising strategy to control progression of MS is the inhibition of the enzyme Bruton's tyrosine kinase (BTK), which is centrally involved in the activation of both B cells and myeloid cells, such as macrophages and microglia. The benefit of BTK inhibition by evobrutinib was shown as we observed reduced pro-inflammatory activation of microglia when treating chronic experimental autoimmune encephalomyelitis (EAE) or following the adoptive transfer of activated T cells. Additionally, in a model of toxic demyelination, evobrutinib-mediated BTK inhibition promoted the clearance of myelin debris by microglia, leading to an accelerated remyelination. These findings highlight that BTK inhibition has the potential to counteract underlying chronic progression of MS.
在多发性硬化症(MS)中,持续性残疾的发生可能与复发活动或新的中枢神经系统(CNS)炎性病变的发展无关,这被称为慢性进展。这一过程发生较早,主要由中枢神经系统内的细胞驱动。抑制布鲁顿酪氨酸激酶(BTK)是控制多发性硬化症进展的一种很有前景的策略,该酶主要参与 B 细胞和骨髓细胞(如巨噬细胞和小胶质细胞)的活化。在治疗慢性实验性自身免疫性脑脊髓炎(EAE)或活化T细胞收养性转移后,我们观察到小胶质细胞的促炎性活化减少,这证明了evobrutinib抑制BTK的益处。此外,在毒性脱髓鞘模型中,evobrutinib介导的BTK抑制促进了小胶质细胞对髓鞘碎片的清除,从而加速了髓鞘再形成。这些发现突出表明,抑制 BTK 有可能抵消多发性硬化症潜在的慢性进展。
{"title":"BTK inhibition limits microglia-perpetuated CNS inflammation and promotes myelin repair","authors":"Anastasia Geladaris, Sebastian Torke, Darius Saberi, Yasemin B. Alankus, Frank Streit, Sabrina Zechel, Christine Stadelmann-Nessler, Andreas Fischer, Ursula Boschert, Darius Häusler, Martin S. Weber","doi":"10.1007/s00401-024-02730-0","DOIUrl":"https://doi.org/10.1007/s00401-024-02730-0","url":null,"abstract":"<p>In multiple sclerosis (MS), persisting disability can occur independent of relapse activity or development of new central nervous system (CNS) inflammatory lesions, termed chronic progression. This process occurs early and it is mostly driven by cells within the CNS. One promising strategy to control progression of MS is the inhibition of the enzyme Bruton's tyrosine kinase (BTK), which is centrally involved in the activation of both B cells and myeloid cells, such as macrophages and microglia. The benefit of BTK inhibition by evobrutinib was shown as we observed reduced pro-inflammatory activation of microglia when treating chronic experimental autoimmune encephalomyelitis (EAE) or following the adoptive transfer of activated T cells. Additionally, in a model of toxic demyelination, evobrutinib-mediated BTK inhibition promoted the clearance of myelin debris by microglia, leading to an accelerated remyelination. These findings highlight that BTK inhibition has the potential to counteract underlying chronic progression of MS.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140642714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-20DOI: 10.1007/s00401-024-02731-z
Ann-Kristin Afflerbach, Anne Albers, Anton Appelt, Leonille Schweizer, Werner Paulus, Michael Bockmayr, Ulrich Schüller, Christian Thomas
{"title":"Nanopore sequencing from formalin-fixed paraffin-embedded specimens for copy-number profiling and methylation-based CNS tumor classification","authors":"Ann-Kristin Afflerbach, Anne Albers, Anton Appelt, Leonille Schweizer, Werner Paulus, Michael Bockmayr, Ulrich Schüller, Christian Thomas","doi":"10.1007/s00401-024-02731-z","DOIUrl":"https://doi.org/10.1007/s00401-024-02731-z","url":null,"abstract":"","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140622790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-19DOI: 10.1007/s00401-024-02720-2
Evan Udine, Mariely DeJesus-Hernandez, Shulan Tian, Sofia Pereira das Neves, Richard Crook, NiCole A. Finch, Matthew C. Baker, Cyril Pottier, Neill R. Graff-Radford, Bradley F. Boeve, Ronald C. Petersen, David S. Knopman, Keith A. Josephs, Björn Oskarsson, Sandro Da Mesquita, Leonard Petrucelli, Tania F. Gendron, Dennis W. Dickson, Rosa Rademakers, Marka van Blitterswijk
The most prominent genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) is a repeat expansion in the gene C9orf72. Importantly, the transcriptomic consequences of the C9orf72 repeat expansion remain largely unclear. Here, we used short-read RNA sequencing (RNAseq) to profile the cerebellar transcriptome, detecting alterations in patients with a C9orf72 repeat expansion. We focused on the cerebellum, since key C9orf72-related pathologies are abundant in this neuroanatomical region, yet TDP-43 pathology and neuronal loss are minimal. Consistent with previous work, we showed a reduction in the expression of the C9orf72 gene and an elevation in homeobox genes, when comparing patients with the expansion to both patients without the C9orf72 repeat expansion and control subjects. Interestingly, we identified more than 1000 alternative splicing events, including 4 in genes previously associated with ALS and/or FTLD. We also found an increase of cryptic splicing in C9orf72 patients compared to patients without the expansion and controls. Furthermore, we demonstrated that the expression level of select RNA-binding proteins is associated with cryptic splice junction inclusion. Overall, this study explores the presence of widespread transcriptomic changes in the cerebellum, a region not confounded by severe neurodegeneration, in post-mortem tissue from C9orf72 patients.
{"title":"Abundant transcriptomic alterations in the human cerebellum of patients with a C9orf72 repeat expansion","authors":"Evan Udine, Mariely DeJesus-Hernandez, Shulan Tian, Sofia Pereira das Neves, Richard Crook, NiCole A. Finch, Matthew C. Baker, Cyril Pottier, Neill R. Graff-Radford, Bradley F. Boeve, Ronald C. Petersen, David S. Knopman, Keith A. Josephs, Björn Oskarsson, Sandro Da Mesquita, Leonard Petrucelli, Tania F. Gendron, Dennis W. Dickson, Rosa Rademakers, Marka van Blitterswijk","doi":"10.1007/s00401-024-02720-2","DOIUrl":"https://doi.org/10.1007/s00401-024-02720-2","url":null,"abstract":"<p>The most prominent genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) is a repeat expansion in the gene <i>C9orf72</i>. Importantly, the transcriptomic consequences of the <i>C9orf72</i> repeat expansion remain largely unclear. Here, we used short-read RNA sequencing (RNAseq) to profile the cerebellar transcriptome, detecting alterations in patients with a <i>C9orf72</i> repeat expansion. We focused on the cerebellum, since key <i>C9orf72</i>-related pathologies are abundant in this neuroanatomical region, yet TDP-43 pathology and neuronal loss are minimal. Consistent with previous work, we showed a reduction in the expression of the <i>C9orf72</i> gene and an elevation in homeobox genes, when comparing patients with the expansion to both patients without the <i>C9orf72</i> repeat expansion and control subjects. Interestingly, we identified more than 1000 alternative splicing events, including 4 in genes previously associated with ALS and/or FTLD. We also found an increase of cryptic splicing in <i>C9orf72</i> patients compared to patients without the expansion and controls. Furthermore, we demonstrated that the expression level of select RNA-binding proteins is associated with cryptic splice junction inclusion. Overall, this study explores the presence of widespread transcriptomic changes in the cerebellum, a region not confounded by severe neurodegeneration, in post-mortem tissue from <i>C9orf72</i> patients.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140622792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-18DOI: 10.1007/s00401-024-02726-w
Esmat Karimi, Jochen Gohlke, Mila van der Borgh, Johan Lindqvist, Zaynab Hourani, Justin Kolb, Stacy Cossette, Michael W. Lawlor, Coen Ottenheijm, Henk Granzier
Nebulin, a critical protein of the skeletal muscle thin filament, plays important roles in physiological processes such as regulating thin filament length (TFL), cross-bridge cycling, and myofibril alignment. Pathogenic variants in the nebulin gene (NEB) cause NEB-based nemaline myopathy (NEM2), a genetically heterogeneous disorder characterized by hypotonia and muscle weakness, currently lacking curative therapies. In this study, we examined a cohort of ten NEM2 patients, each with unique pathogenic variants, aiming to understand their impact on mRNA, protein, and functional levels. Results show that pathogenic truncation variants affect NEB mRNA stability and lead to nonsense-mediated decay of the mutated transcript. Moreover, a high incidence of cryptic splice site activation was found in patients with pathogenic splicing variants that are expected to disrupt the actin-binding sites of nebulin. Determination of protein levels revealed patients with either relatively normal or markedly reduced nebulin. We observed a positive relation between the reduction in nebulin and a reduction in TFL, or reduction in tension (both maximal and submaximal tension). Interestingly, our study revealed a pathogenic duplication variant in nebulin that resulted in a four-copy gain in the triplicate region of NEB and a much larger nebulin protein and longer TFL. Additionally, we investigated the effect of Omecamtiv mecarbil (OM), a small-molecule activator of cardiac myosin, on force production of type 1 muscle fibers of NEM2 patients. OM treatment substantially increased submaximal tension across all NEM2 patients ranging from 87 to 318%, with the largest effects in patients with the lowest level of nebulin. In summary, this study indicates that post-transcriptional or post-translational mechanisms regulate nebulin expression. Moreover, we propose that the pathomechanism of NEM2 involves not only shortened but also elongated thin filaments, along with the disruption of actin-binding sites resulting from pathogenic splicing variants. Significantly, our findings highlight the potential of OM treatment to improve skeletal muscle function in NEM2 patients, especially those with large reductions in nebulin levels.
{"title":"Characterization of NEB pathogenic variants in patients reveals novel nemaline myopathy disease mechanisms and omecamtiv mecarbil force effects","authors":"Esmat Karimi, Jochen Gohlke, Mila van der Borgh, Johan Lindqvist, Zaynab Hourani, Justin Kolb, Stacy Cossette, Michael W. Lawlor, Coen Ottenheijm, Henk Granzier","doi":"10.1007/s00401-024-02726-w","DOIUrl":"https://doi.org/10.1007/s00401-024-02726-w","url":null,"abstract":"<p>Nebulin, a critical protein of the skeletal muscle thin filament, plays important roles in physiological processes such as regulating thin filament length (TFL), cross-bridge cycling, and myofibril alignment. Pathogenic variants in the nebulin gene (<i>NEB</i>) cause NEB-based nemaline myopathy (NEM2), a genetically heterogeneous disorder characterized by hypotonia and muscle weakness, currently lacking curative therapies. In this study, we examined a cohort of ten NEM2 patients, each with unique pathogenic variants, aiming to understand their impact on mRNA, protein, and functional levels. Results show that pathogenic truncation variants affect <i>NEB</i> mRNA stability and lead to nonsense-mediated decay of the mutated transcript. Moreover, a high incidence of cryptic splice site activation was found in patients with pathogenic splicing variants that are expected to disrupt the actin-binding sites of nebulin. Determination of protein levels revealed patients with either relatively normal or markedly reduced nebulin. We observed a positive relation between the reduction in nebulin and a reduction in TFL, or reduction in tension (both maximal and submaximal tension). Interestingly, our study revealed a pathogenic duplication variant in nebulin that resulted in a four-copy gain in the triplicate region of NEB and a much larger nebulin protein and longer TFL. Additionally, we investigated the effect of Omecamtiv mecarbil (OM), a small-molecule activator of cardiac myosin, on force production of type 1 muscle fibers of NEM2 patients. OM treatment substantially increased submaximal tension across all NEM2 patients ranging from 87 to 318%, with the largest effects in patients with the lowest level of nebulin. In summary, this study indicates that post-transcriptional or post-translational mechanisms regulate nebulin expression. Moreover, we propose that the pathomechanism of NEM2 involves not only shortened but also elongated thin filaments, along with the disruption of actin-binding sites resulting from pathogenic splicing variants. Significantly, our findings highlight the potential of OM treatment to improve skeletal muscle function in NEM2 patients, especially those with large reductions in nebulin levels.</p>","PeriodicalId":7012,"journal":{"name":"Acta Neuropathologica","volume":null,"pages":null},"PeriodicalIF":12.7,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140620549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}